Denzel had worked at the security company Blackwell and Brothers since he was 20. However, though he was often the one of the more competent of his colleagues, he was always abused by his bosses and co-workers, primarily due to his poor social skills and seeming absent-mindedness. Eventually, when he was 32, his new boss began to try to break him down, out of the company, as he was family to one of the board members, and thought Denzel had slighted him. Getting a few other employees with him, they began to abuse Denzel.
After two years, it was enough. He snapped. Visiting the armory, he picked up a hand laser and a combat knife, and went on a rampage through the office his boss worked at, killing over two dozen employees, including his boss. Needless to say, the family ties his dead boss had weren’t very friendly, and soon Denzel found himself headed to the HMRC.

Reason assigned to HMRC: Mass-murder of over two dozen people in an office complex in a fit of rage.